Process of gas generation.



No. 795,257. PATENT'ED JULY 18, 1905. B. E. BLDRED & G. ELLIS. PROCESS OF GAS GENERATION.

APPLIOATION FILED P338. 1905.

NITED STATES Patented July 18, 1905.

PATENT OFFICE.

BYRON E. ELDRED AND CARLETON ELLIS, OF NEWV YORK, N. Y., ASSIGNORS TO ELDRED PROCESS COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEWV YORK.

PROCESS OF GAS GENERATION.

SPECIFICATION forming part of Letters Patent No. 795,257, datedy 18, 1905.

Application filed February 8, 1905. Serial No. 244,660.

To all whom it may concern:

Be it known that we, BYRON E. ELDRED and CARLETON ELLIs, citizens of the United States, and residents of New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Processes of Gas Generation, of which the following is a specification.

Our invention relates to the art of making gas by the gas-producer process as distinguished from the retort or water-gas processes.

It relates to that branch of the art wherein the gas-producer is functionally remote from the consuming apparatus and may therefore be an independent structure, although inclependence of structure is not essential to our invention, and it is possible to combine the gas-producing and consuming apparatus in a single structure, provided its organization he 0 such as to preserve the essential functional characteristics. In the practice of this art it has been customary to employ a thick bed of fire in order that the carbon dioXid formed by combustion in the lower layers may pass through the hot layers above to be there reduced to carbon monoxid, one of the atoms of oxygen splitting ofi of each molecule and joining with an atom of carbon of the coal, thus making two molecules or two volumes of 3 carbon monoxid from one molecule or volume of carbon dioxid. It has also been the practice to employ steam to regulate the temperature of this fire-bed. This process relates to a method for the endothermic control of gas-producers by means of the carbon dioxid in place of steam as the cooling agent.

The present invention relates particularly to the use of gases carrying carbon dioxid as obtained from a limekiln for the control of 4 gas constitution and of the temperature of gas generation.

In the complete reduction of the oxygen of the air by means of carbon to carbon dioxid, the products of combustion carry approxiniately twenty-one per cent. of carbon dioxid and seventy-nine per cent. nitrogen. When,

however, carbon dioXid is evolved by the decomposition of materials undergolng reactionsuch, for instance, as occurs in the calcination of limestone the products of combustion may contain more than twenty-one per cent. of carbon dioXid. The increase in the percentage of carbon dioXid means a de crease in the percentage of the accompanying inert gas, nitrogen. As this gas goes through any heating system unchanged and as it has of course a certain heat-absorbing capacity, a reduction in the amount of nitrogen is a desideratum.

Our process as hereinafter described sets forth a method for using the gases of a limekiln for the regulation and control of the temperature of the gas-producer, by means of which a reduction to an eflicient low temperature plane may be secured, whereby the production of an objectionable amount of soot and clinker in the gas-producer is efiiected and whereby a gas of exceedingly high calorific value may be obtained without the use of any steam whatsoever in the operation of the producer.

Our invention consists in removing from the limekiln at or near the top of the kiln, the gases of combustion and of decomposition of the limestone, in causing these gases to pass through a conduit or passage to the gasproducing appliance, and in passing these gases through a mass of ignited fuel, at the same time admitting to the producer sufficient air to regulate the intensity of the combustion, and in causing the combustible gas so produced to be introduced in a furnace or kiln, such as a limekiln, and to be burned by the addition of the requisite amount of air, which, moreover, may be heated, if desired, before its admixture with the combustible gas.

In the accompanying drawing apparatus is diagrammatically shown which illustrates our process.

1 is a limekiln consisting ordinarily of a vertical shaft lined with refractory material. At the upper part 2 the limestone is introduced.

3 is a cooler from which the calcined product is withdrawn. At a point near the top of the kiln (shown at 4.) a conduit 6 leads to the a relatively high temperature.

producer interposed in this conduit is a suction-fan 7, having an air-inlet 8. The cond uit on the outlet side of the fan connects with the gas-producer 5 at 1%, from which point the drz'lft-gases may be distributed through the fuel in any approved manner. A passage 10 connects the gas-producer with the limekiln 1. An air-inlet 12 serves to admit air to the burner at 15. Regulation of the amount of air and carbon dioxid or stack-gas ad mitted to the gas-producer is effected by the adjustmentof valves orgates 9, 13,18, 11, and 16.

The method of operation is as follows: Assume the kiln to be at the working temperature, limestone being heated and calcined in the upper parts of the kiln and withdrawn in the l gver part. Products of combustion are drawn back through pipe 6, air is introduced at inlet 8, and this mixture of stack-gas and air is blown into the producer, in which a deep bed of incandescent fuel is maintained. Adjustment of the valves 9 and 13 is made to secure the proper temperature in the gas-producer. Admission of carbon dioxid in a greater or less quantity, together with the proper proportioning of the air supplied by means of the aforesaid valves, constitutes the adjustment for temperature. The varying nature of the fuel and the different clinkering or sooting points of various coals make it impossible to lay down any definite proportion for these gaseous mixtures. From the description herewith given it will be evident to one skilled in the art to which the invention appertains the manner in which this control may be effected. The combustible gas passes,

as herewith shown, from the gas-producer to a limekiln. After ignition at the burners 15 in the presence of a supply of air admitted by opening the damper 16 a flame of great heat-imparting quality is produced, suitable for lime-burning and for other heating operations. Steam-jets (shown at 17) may be used for operating the gas-producer in case the fan be temporarily disabled or in the operation of starting up the kiln when the gases derived therefrom may be of uncertain composition, making it impossible to properly adjust the temperature of the producer by carbon dioxid until the operation of the kiln, as shown by the products of combustion therefrom, indicates uniformity of working. It may be found at times desirable to use a steam-jet for inducing air or for regulating the temperature of the producer, although the use of steam is not to be recommended because of the element, hydrogen, introduced into the combustible gas and because of the impossibility of running the producer at a satisfactory temperature when steam is used as the cooling agent, owing to the fact that its decomposition takes place only at Hence such a use of steam is undesirable, except in starting to heat the kiln or in an emergency, as already be preheated by any suitable or well-known form of heating device -such, for instance, as a stove placed at the top of the kiln or at any point where it may utilize the waste heat of the products of combustion. in case the air be preheated to such an extent that too high a temperature is produced in that part of the kiln where the air and combustible gas unite the temperature of the flame may be reduced by the addition of products of combustion to the gas prior to its entrance into the kiln. The carbon dioxid and products of combustion serve to temper the flame and to increase its volume, as is well known in the art, the method being described in United States Patent No. 692,257. e do not limit ourselves to the particular form of application of our process, as herein described. The idea set forth is applicable to many types of heating appliances. Furthermore, it is not necessary to resort to any special form of producer. A downdraft producer, for instance, may be used as well as the updraft sort herewith shown.

Our process delivers a gas of high calorific value, low in nitrogen, and it consequently has great heating power. It calcines limestone most effectively with a minimum of cost of fuel. The inability heretofore experienced in operating gas-producers to cheaply supply combustible gas for burning lime has been due to the fact that steam has been the endothermic material employed in the producer. Hence the impossibility of utilizing most of the heat of primary combustion-that is to say, that heat developed by the combustion of carbon dioxid to carbon monoxid in the gas-producer for conversion into latent energy of combustible gas. Our process involves the use of the products of combustion carrying abnormal amounts of carbon dioxid obtained from the decomposition of limestone, securing an economy of operation of the producer which renders it of great commercial value for the purpose aforesaid.

What we claim is 1. Process of generating combustible gas which consists in drawing products of com-- bustion rich in carbon dioxid from a limekiln and in adding same to the gas-generating airblast in an amount sufiicient to depress the temperature of the gas-generating fire below the slagging-point of the fuel, in continuously passing the gaseous mixture through a thick bed of fuel, constituting said gas-generating fire, to form a combustible-gas-containing carbon monoxid largely in excess of hydrogen and in conveying the gas so produced to the place of consumption.

2. In the generation of combustible producer-gas relatively low in hydrogen and nitrogen, the process which consists in continuously passing through a flameless mass of ignited coal. a draft-current composed of air stated. The air entering the burner at 15 may i and products of combustion from the calcination of lime, in such proportionate amounts as will serve to maintain the ignition of the gas-generating fire while depressing the temperature of said fire below the clinkeringpoint of the coal, in collecting the combustible gas so produced and in conveying it without the addition of air or oxygen to a point remote from the seat of generation.

3. In the generation of combustible producer-gas relatively low in hydrogen and nitrogen, the process which consists in con tinuously passing through a fiameless mass of ignited coal a draft-current composed of air and products of combustion from the calcination of lime, in such proportionate amounts as Will serve to maintain the ignition of the gas-generating fire While depressing the temperature of said fire below the clinkeringpoint of the coal, and in conveying to the limekiln and in there burning such portion of the gas so generated as is required for the calcination of the lime.

Signed at New York city, in the county of New York and State of New York, this 6th day of February, A. D. 1905.

BYRON E. ELDRED GARLETON ELLIS. Witnesses:

J AS. K. CLARK, M. F. MANGELSDORIF. 

